Saunier Duval Thema F23E boiler producing luke warm water

gfh219 · 3 Aug 2009

I have a 10 year old Saunier Duval Thema F23E combi boiler for hot water and central heating.

Recently it has started to produce luke warm water which initially is cloudy in colour but the flow of water is good.
The radiator heat seems to be fine.

I have had the boiler re-pressurised and when it is on it reaches approx 1.5 bar. I have even replaced the thermister as someone told me that could be causing it but the water is still running luke warm.

Does anyone know what might be causing the water to run luke warm and cloudy?

Any advice would be gratefully appreciated.

Many thanks

Agile · 3 Aug 2009

Not my favourite boiler make!

It sounds as if the secondary side of the water heat exchanger has become scalled up.

Have you had any leaking taps or pipes?

Tony

gfh219 · 3 Aug 2009

No, I haven't noticed any leaking taps or pipes.
Just the luke warm and cloudy water.

Presumably scaling would be the reason why the water is coming out cloudy?

Agile · 3 Aug 2009

I doubt it.

It comes out cloudy because of the reduction in pressure as a result of air bubbles and will clear after a few seconds in a glass.

But it may be an indication of a restriction caused by lime scale causing a more violent expansion to atmospheric pressure.

Tony

gfh219 · 3 Aug 2009

So basically Tony, sounds like we need to descale the heat exchanger.

Is it best to get it descaled or just replace it all together?

Thanks G

Deleted member 105431 · 3 Aug 2009

gfh219 said:
So basically Tony, sounds like we need to descale the heat exchanger.

Is it best to get it descaled or just replace it all together?

Thanks G

best to get a new boiler; these are cheap and nasty french junk.

jay1 · 3 Aug 2009

turn the hot taps on and see if heating flow pipes get hot.

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Saunier Duval Thema F23E boiler producing luke warm water

gfh219

Agile

gfh219

Agile

gfh219

Deleted member 105431

jay1

DIYnot Local

Similar threads